https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94025
--- Comment #2 from Daniel Krügler <daniel.kruegler at googlemail dot com> --- (In reply to Daniel Krügler from comment #1) [..] > I'm surprised that the Visual Studio compiler (I tested 2019) rejects the > original example, this looks like a bug to me, especially since that > compiler also handles the call resolution for the above defined Lambda type > correctly. I plan to report an issue for that compiler. I have opened a corresponding bug report against the VS 2019 compiler: https://developercommunity.visualstudio.com/content/problem/990374/conversion-function-to-function-pointer-for-mutabl-1.html